SudokuHard

Hard Sudoku — Puzzle 238

815
3
578
864
64395
53
41
396
1642

How to play

Fill every row, every column and every 3 by 3 box with the numbers 1 to 9, using each number once.

This puzzle has 26 given numbers and exactly one solution, so it can always be finished by reasoning alone.

876134259
452798136
139256748
718562394
624389517
593417862
265843971
347921685
981675423